Abstract: The cooling rate and temperature uniformity of the model in the test chamber of the thermal cycle system are investigated numerically under different structural parameters.Results show that when the model is located at the center of the test chamber,due to the obstruction of the model,a stagnation zone appears on the surface of the model,and a high temperature recirculation zone is generated at the bottom of the model.The cooling rate of the model is gradually increased with the increase of the distance between the model and the ground,and the cooling process can be completed within 7 h,In contrast with D=1.0 m,the maximum temperature standard deviation is reduced to 25%,when D=5.0 m.By changing the shape of the model,the size of the recirculation area can be reduced,thereby accelerating the cooling process.Compared with the air supply method in the vertical direction,the lateral ventilation is more conducive to the cooling process.The lateral ventilation can significantly increase the cooling rate,and can significantly improve the temperature uniformity,and reduce the maximum temperature standard deviation to 40%of the vertical air supply method.